1. Field of the Invention
The present invention relates generally to an automatic document feeder for a scanning device and, more particularly, to a method for applying a pick retry using a modified pick roller force to reduce the likelihood of failure to pick the top sheet from a media stack.
2. Description of the Related Art
It is common for an automatic document feeder (ADF) for a scanning device to include a pick roller to move the top sheet of an input media stack into the ADF feed path. There are different methods for engaging the pick roller to the input media, but the desired result is the same. The pick roller should move only the top sheet of the input media. There is an operating window for the pick roller to ensure enough force is created to move the top sheet, but not too much such that subsequent sheets are not moved. Thus, it is common for the pick roller to have just enough force to move the top sheet of the input media stack.
In some cases, it is possible that this force is not great enough and the ADF fails to move the top sheet far enough to the media path and reports a jam. It is also possible that the input media condition is not ideal, and this undesired condition of the media creates problems when trying to move the top sheet of the input stack. Thus, it is common for some ADF devices to incorporate a retry of the pick roller if it fails to feed the top sheet. However, it is possible that the retry of the pick roller will turn out to be ineffective also and thus end in failure.
Thus, there is still a need for an innovation that will establish a parameter that will ensure the success of the retry of the pick roller in response to its failure to feed the top sheet.